High-Power, High-Efficiency GaN HEMT Power Amplifiers for 4G Applications

Download Whitepaper
  • Author: Simon Wood, Ray Pengelly, Don Farrell, Carl Platis, and Jim Crescenzi
Today’s wireless system requirements demand increasing performance from power amplifiers. The higher gain and output power available from today’s transistors reduce the number of amplifier stages, and improved efficiency decreases system DC power requirements and generated heat. But at these higher power and efficiency levels, power amplifier linearity needs to meet or exceed the requirements of past systems. Gallium nitride (GaN) HEMT based power transistors offer an ideal technology solution for these amplifiers due to their exceptionally high operating power density. Cree’s GaN HEMT devices deliver RF power densities as high as 8 W/mm of gate periphery due to superior thermal properties provided by the silicon carbide substrates on which they are fabricated. This is of considerable advantage when compared with silicon substrates. This article details three amplifier designs that cover a variety of 4G frequency bands.